AK, Overbridge & Nuendo : control ok but no sound

Hi Elektronauts,

I’m trying to use my AK in Nuendo using Overbridge.
Everything works fine except… audio ! I mean I can control the Overbridge panel from the AK but I have no sound reaching Nuendo’s mixer. I also have a strange warning message in the Overbridge panel :
“Your host audio buffer size is 512 samples. It is recommended that you use 256 samples or lower. Please re-configure your host.”
The point is that I’m using 128 samples buffer size so Overbridge is reporting something wrong. I use 2 RME Digiface sound cards on Win10.
Overbridge is working good in stand-alone mode
Any idea ?

Thanks for your help.